The present invention relates to a communication system, comprising a network, one or more optical transmitters and potential noise sources.
The present invention also relates to filter means for application in the communication system.
Such a communication system and filter means are known from U.S. Pat. No. 5,142,690. The known communication system is particularly concerned with upstream communication in a typical cable television (CATV) system, that is in return direction from subscriber to head end. Such a system is further known to have possible fibre optic means, such as optical transmitters, which may well known be included in its trunk lines, such as the trunk line 141 in FIG. 1 thereof. Said upstream communication is subjected to serious and accumulating, so called ingress noise emanating from a variety of types of noise sources such as impulse noise sources, in particular in-home or external noise sources, which have a impulse-like behavior, meaning that this noise varies with time and generally lasts up to several milliseconds. Examples of such impulse noise sources are switches, lighting, machines, such as washing machines, drying machines, refrigerators, magnetrons, communication devices, such as mobile telephones, facsimiles, printers, computers, displays, ignitions, radio stations etcetera. During periods of noise interference the upstream communication may, apart from being disturbed be completely blanked-out. After the blank-out period synchronization has to be re-established in order to recover from a period of lack of communication. This reduces the upstream data transfer rate of the known communication system and leads to undue communication delays.